The Specialized bikes have very steep seat tube angles (76 degrees) on the smaller bikes. On their 54 cm frame the seat tube angle is 74 degrees.

Cannondale has the 75 degree seat tube angle on the Synapse but they don't make it any smaller than 47 and its interesting to note that on their 40 and 44 cm frames they still use 650c wheels.

Caligurl, I'm getting the feeling that a lot of the small custom builders will not put 700c wheels on a small frame. Some won't bother making a 650c wheel frame.

I didn't push the issue but I suspect that Serotta would not have built my 48 cm custom frame for 700c wheels.

I wonder about a 74 degree seat tube angle on a bigger frame because my 48cm frame has a 74.5 degree seat tube angle. It just seems like a bigger frame should have a slacker seat tube angle.

I think the steeper seat tube angles are how Specialized is getting around the toe overlap issue. I wonder if the rider's center of mass is then compromised?